Today, animal-based research continues to play a key role in the development of medicine and medical technology. Because all mammals share certain biological features, like having a backbone or using lungs to breathe, many processes that exist in the human body can be studied in animals. For example, much of what is known about our immune system comes from our research on mice. Studies of sheep and dogs have contributed to our understanding of the cardiovascular system. Such studies can be even more effective if scientists use “designer” animals. These animals are genetically modified to allow researchers to target a particular disease. For example, Harvard University’s OncoMouse® carries a gene that encourages the growth of certain human cancers.

Another advantage of animal-based research is that it allows scientists to test new surgical procedures or medical products without risking human suffering or loss of life. One important example of this is the toxicology test. This test is used to determine whether or not particular chemicals are harmful to humans. Although it frequently causes a great deal of pain and suffering in the animal test subjects, it is necessary for many researchers who need to know whether or not certain substances are safe for humans.